A company needs employees who work remotely to have secure access to the corporate intranet. Which of the following should the company implement?

A Virtual Private Network (VPN) is the standard technology for providing secure remote access to a private network over a public one, like the internet. It establishes an encrypted tunnel between the remote employee's device and the corporate network's VPN concentrator. This tunnel encrypts all data traffic, ensuring confidentiality and integrity, and makes the remote device appear as if it is on the local corporate network, granting it secure access to internal resources such as the intranet.

A. Password-protected Wi-Fi only secures the local wireless link between the user's device and their local router, not the connection across the internet to the company.
B. Port forwarding is used to direct external traffic to a specific device on an internal network, which can create security vulnerabilities and does not provide a secure, comprehensive connection to the entire intranet.
D. A perimeter network (or DMZ) is a buffer subnetwork that hosts external-facing services, isolating them from the secure internal network. It is designed to protect the intranet, not grant remote users access to it.

1. Microsoft Corporation. (2023). What is VPN? How it works, types of VPN. Microsoft Learn. In the section "How does a VPN work?", it states, "A VPN works by creating an encrypted connection over the internet from a device to a network... This secure connection helps ensure that sensitive data is safely transmitted."

2. Carnegie Mellon University. (n.d.). Virtual Private Network (VPN). Computing Services. Retrieved from cmu.edu. The documentation states, "A Virtual Private Network (VPN) provides a secure connection between your computer and the campus network from a remote location." This exemplifies the primary use case for VPNs in an organizational context.

3. Dordal, P. L. (2019). An Introduction to Computer Networks (2nd ed.). Chapter 14, Network Security. In section 14.7, "Virtual Private Networks," the text describes VPNs as a mechanism to "allow the computers of a given site to connect to the private network for that site via a secure 'tunnel' through the Internet."

4. National Institute of Standards and Technology (NIST). (2020). Guide to Enterprise Telework, Remote Access, and Bring Your Own Device (BYOD) Security (NIST Special Publication 800-46 Rev. 2). In Section 3.2.1, "Virtual Private Networks," it is stated that "A VPN provides a virtual network connection that encapsulates and encrypts traffic... This allows a remote host to securely access resources on its organization’s network as if the host were physically connected to the network." (Page 15).